The photoelectric effect is a phenomenon first discovered by Heinrich Hertz in 1887. The photoelectric effect, when first discovered was a huge step forward for physicists. It not only helped to further discover the quantum nature of photons and electrons but it also gave physicists another stepping stone in terms of the long debated wave-particle duality feud of light. Basically the Photoelectric Effect is a phenomena where a photon of light with a certain energy level, strikes a particular metal and becomes absorbed, then releases an electron. An important note on the photoelectric effect is that for every one photon absorbed, one electron is emitted and also that intensity of light does not increase energy in each electron but only the amount of electrons that are released.

The Photoelectric Effect can be summed up by the equation; EK(max) = hf - W

EK(max)- Maximum kinetic energy of the emitted electron.
h- Refers to Planck's constant. (4.14E-15 eVs or 6.63E-34 Js)
f- Refers to the frequency of the incident photon.
W- Refers to the work function, composed of the threshold frequency and again Planck's constant.

The threshold frequency is the minimum frequency needed by the photon in order for an electron to be emitted from the metal. Therefore in order for an electron to be emitted from the metal hf > W.

Another important part of the Photoelectric Effect is the stopping voltage, or amount of voltage needed to inhibit the emission of a photoelectron.
This can be represented by the equation; E = qV(stop)

E- The total possible energy carried by the electron.
q- The charge of the electron. (Elementary charge = 1.60E-19c)
V(stop)- The stopping voltage or amount of voltage needed in order to halt the photoelectron emission.
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